In many types of constructions, particularly marine-type constructions such as barges, tanks, and ships, angle irons are utilized to stiffen bulkhead plates against hydrostatic pressure that the plates will encounter in use. The angle irons are usually welded to the plates so that one arm of the angle iron extends horizontally and is attached to the plate (which comprises a wall means), while the other arm of the angle iron extends generally vertically and is spaced from the plate. The angles are usually placed on 24 inch spaced increments. During construction and repair procedures, workers use the angles as ladders to climb the walls of the tank, ship, or the like.
According to the present invention a safety belt anchor system, and an anchoring procedure, are provided which minimize the chances of worker injury due to a fall off the angle irons when the worker is working at elevated areas. The structure according to the invention is extremely simple to attach in place, requiring only one-hand operation. Yet the anchor is extremely effective, and will not slip should the worker fall, and the force of his fall will be transmitted to the anchor by a safety belt.
The anchoring structure according to the invention includes a conventional vise grips, having a stationary jaw, a movable jaw, jaw movement lever means, and adjustment means for adjusting the spacing between the jaws when in a clamping position. An imaginary line extends substantially parallel to the jaws, and between the jaws, when they are in the clamping position. The structure further comprises a head which is welded, or otherwise affixed, to the stationary jaw, and includes force concentrating means associated therewith. Preferably, the head includes a flange surface which extends substantially perpendicular to the imaginary line, with the force concentrating means preferably comprising pointed set screws--passing through the flange surface at an acute angle (e.g. about 15 degrees) to the imaginary line. A through-extending opening for receiving the clasp of a safety belt--or other safety belt attachment means--is associated with the head.
In utilizing the safety belt anchor according to the invention, a worker climbs up the angle irons to the desired work area and then with one hand moves the anchor into position with respect to an angle iron that is at, or above, the desired work area. The set screws are moved into contact with the horizontally extending arm of the angle iron, while the stationary jaw is moved into contact with the vertically extending arm of that angle iron. Then the worker--with one hand--actuates the movable jaw lever, so that the movable jaw moves into position against the angle iron vertically extending arm, clamping the vertically extending arm between it and the stationary jaw.
If desired, two safety anchors may be utilized that are horizontally spaced, with a safety belt hooked to each.
It is the primary object of the present invention to provide an easy to use, and effective, safety anchor--and method of utilization thereof--for utilization with structural angle irons. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.